Index: /CKEditor/trunk/_source/plugins/scayt/plugin.js
===================================================================
--- /CKEditor/trunk/_source/plugins/scayt/plugin.js	(revision 5501)
+++ /CKEditor/trunk/_source/plugins/scayt/plugin.js	(revision 5502)
@@ -58,5 +58,5 @@
 			oParams.onBeforeChange = function()
 			{
-				if ( !editor.checkDirty() )
+				if ( plugin.getScayt( editor ) && !editor.checkDirty() )
 					setTimeout( function(){ editor.resetDirty(); } );
 			};
@@ -156,8 +156,8 @@
 				var editor = ev.editor,
 					scayt_instance = plugin.getScayt( editor );
+				delete plugin.instances[ editor.name ];
 				// store a control id for restore a specific scayt control settings
 				scayt_control_id = scayt_instance.id;
 				scayt_instance.destroy( true );
-				delete plugin.instances[ editor.name ];
 			});
 
@@ -166,5 +166,9 @@
 			{
 				if ( plugin.isScaytEnabled( editor ) ) {
-					window.setTimeout( function(){ plugin.getScayt( editor ).refresh(); }, 10 );
+					window.setTimeout( function()
+						{
+							var instance = plugin.getScayt( editor );
+							instance && instance.refresh();
+						}, 10 );
 				}
 			});